GDAL 1.5.0 and GEOS 3.0.0 were released during the holiday and are now used in the Knowhere and Gdawg buildouts. The big change in GDAL is new Python bindings. The ones that Howard Butler has been calling the next generation bindings are now the official primary Python bindings. My benchmarks say 1.5.0 is a little (~5%) slower than 1.4.2:
sean@lenny:~/Projects/Gdawg$ ./bin/gdawgpy benchmark.py WorldMill (Cython) 8951.09 usec/pass ogr.py (new bindings) 24846.93 usec/pass
WorldMill remains faster at its tasks. The GDAL/OGR C API hasn't changed in 1.5.0, so WorldMill builds without a hitch.